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After many years of hypertext research, the Dexter model was defined [7] to capture the features of most existing hypertext systems in a single, formal reference model. Likewise, the AHAM model [5] (based on Dexter) describes most features that are found in adaptive hypermedia systems (ahs). In the AHA! project funded by the NLnet Foundation we are extending the simple AHA system [4], [6] with the condition-action rules that were introduced in AHAM [8]. This results in a more versatile adaptation engine, with more intuitive and more powerful rules.

Reuse is a fundamental concept in software design. It has many aspects and can be applied at various levels of abstraction. In this paper we focus on the reuse of highlevel (design model) specifications of software components in the design of web applications. Concretely, we discuss the reuse of navigation templates to specify (parts of) navigation models in different application domains based on different data sources. While supporting this diversity of applications, at the same time navigation templates should allow easy deployment. In this paper we propose a solution to this apparent contradiction using a component-specific conceptual model. By applying a mapping from this model to a concrete domain model, an automatic deployment of the navigation templates can be performed. The process of navigation template design and deployment (including the process of defining the mapping) is explained and demonstrated on two examples using the Hera framework and its HPG software.

This note gives an overview at a high conceptual level of the various databases that capture the information concerning the CMS detector. The detector domain has been split up into four, partly overlapping parts that cover phases in the detector life cycle: construction, integration, configuration and condition, and a geometry part that is common to all phases. The discussion addresses the specific content and usage of each part, and further requirements, dependencies and interfaces.

A new learning environment, called Design-Based Learning (DBL), was incorporated in a Computing Science curriculum, as part of a university-wide process. The aim was to design and implement a series of group projects for the first and second year. The question which design elements could play a role in an early phase of the curriculum was to be examined, and the previously independently offered skills training courses were to be embedded more coherently. In this paper the central topic is the position of skills training in the curriculum. DBL provided the opportunity to practise discipline-related design skills as well as more general skills such as project skills, group skills and communication skills. We will focus upon the general skills. Looking back at the developments in our skills training program, we identify three different stages: isolation, integration and selection. It proved to be important to integrate skills in such a way that students perceive them as useful and to identify core skills. We conclude that in a Computing Science program, the core skill is reporting. Also, skills can have various roles: they can be an end or a means or even both and sometimes this role can change. Finally, we point out that the process of curriculum development has some partly irrational aspects too.

Adaptation in on-line textbooks makes it possible to allow learners to study the textbook in different ways without encountering difficulties. Conditional inclusion of fragments and stretchtext make it possible to provide additional or prerequisite explanations when needed or desired. In this paper we present a new and more flexible way to conditionally include information: adaptive object inclusion. We realize that when applications become more and more dynamic users may start to feel uneasy when the presentation of the same information or concepts changes all the time. We therefore also introduce the idea of stable presentations, a technique to limit the adaptation to information the user has not yet visited. We have implemented both new techniques in the AHA! system.

AHA!, the "Adaptive Hypermedia Architecture", was originally developed to support an on-line course with some user guidance through conditional (extra) explanations and conditional link hiding. This paper describes the many extensions and tools that have turned AHA! into a versatile adaptive hypermedia platform. It also shows how AHA! can be used to add different adaptive "features" to applications such as on-line courses, museum sites, encyclopedia, etc. The architecture of AHA! is heavily inspired by the AHAM reference model.

Virtual enterprises (VEs), in our view, are conglomerates of regular enterprises that collaborate on an ad hoc basis to carry out an inter-organisational business process. The virtual enterprise has a dynamic structure that depends on the particular process that needs to be carried out. Enterprises can join or leave the virtual enterprise at short notice, depending on the capacity and the opportunity. In recent papers, we studied the use of a mobile agent framework to support the co-ordination of the primary process in a virtual enterprise. We argued that the installation of standard software modules, called service bridges or docks, at the participant enterprises provides a suitable infrastructure for the use of mobile agents for this purpose.

AHA! is a simple Web-based adaptive hypermedia system. Because of this simplicity it has been studied and experimented with in several research groups, see e.g. (Cini & Valdeni de Lima, 2002), (Calvi & Cristea, 2002), (Romero et al., 2002). This paper identifies shortcomings in AHA! and presents AHA! version 2.0 which tries to overcome the known problems with AHA! while maintaining its biggest asset: simplicity. We illustrate how different user modeling and adaptation aspects can be expressed in the new AHA! system (that would be difficult in the old system, and impossible in most other systems).

A hypermedia application offers its users a lot of freedom to navigate through a large hyperspace, described by a domain model. Adaptive hypermedia systems (AHS) aim at overcoming possible navigation and comprehension problems by providing adaptive navigation support and adaptive content. The adaptation is based on a user model that represents relevant aspects about the user. In this paper, we concentrate on the adaptation engine (AE) that is responsible for performing the adaptation according to the adaptation rules specified in the adaptation model. We analyze the dependencies between the authoring process and the functionality of the adaptation engine. From this we conclude how the authoring process can be simplified by a more powerful AE. In particular, a well-designed AE should be general purpose (i.e., not application domain specific) and should guarantee that the interpretation of the rules is deterministic, always terminates and produces the results desired by the author.

Business processes are frequently becoming distributed processes. This is due to the emergence of global markets and global manufacturing made possible by improved communications and support from ERP systems. Optimization of business processes requires tuning of the process and application layers, and of the process and infrastructure layers. This requires insight into the consequences of decisions at one layer for another layer. Automated tools for analysis are expected to play an important role in the support of decision making during ERP implementations for distributed businesses. The present paper covers the DIAMond project, its method, cases studied and intermediate results.

The MiViPoRo framework offers a general systematisation of knowledge in domains where work involves the interaction of processes in both the physical domain and the information infrastructure. For the domain of engineering and manufacturing the framework assumes a further division of the cybernetic domain and the physical domain into activity layers for observations and operations (manufacturing), and improvements and innovations (engineering). Mobile software agents, on the other hand, form a new paradigm for the implementation of flexible communication, computation and coordination services in loosely coupled distributed systems. This paper will look into the architectural characteristics of both approaches and it will compare and contrast them. Both approaches are fit for complementary purposes, making their merging an attractive option.

A prototype has been developed of a generic tool set and accompanying methods that enable a customizable approach towards project tracking and benchmarking. The underlying data model describes a generic project life cycle. The prototype has been applied to an iterative development life cycle in a number of field rests.

Dit artikel heeft als ondeiWerp functionele gegevensmodellen. In de inleiding wordt geschetst wat de plaats van deze modellen is binnen het kader van gegevensmodellen. Functionele modellen hebben een belangrijke rol gespeeld bij de ontwikkeling van gegevensmodellen. Een aantal concepten, die binnen het kader van de functionele modellen zijn onderzocht, zijn terug te vinden in latere modellen, zoals de object-georienteerde modellen. Naast de basisingredienten van functionele modellen, die besproken worden aan de hand van het functionele model van Shipman [28], wordt ingegaan op een aantal toepassingen die de mogelijkheden van functionele modellen illustreren. Een aantal ontwikkelingen rond de functionele modellen wordt besproken.

High level communication by means of the exchange of messages between different organizations or organizational units is studied. The concepts of business transaction and business transaction protocol are discussed. Message exchanges are controlled by a message handler that enforces a transaction protocol. The design and implementation of a generic message handler is described. The design is independent of a specific application. It offers a flexible implementation of protocols: dedicated subprocesses handle each message type. Changes in a protocol can easily be accommodated by adapting the subprocesses. A prototype has been written in the executable specification language ExSpect. The protocols can be validated by simulating the message exchange for a number of cases. As an application of the prototype, a party in a logistic chain using EDI is described.

Contains fulltext : mmubn000001_025264788.pdf (Publisher’s version ) (Open Access) Promotor : J. de Swart [VI], 217 p.